It wasn't globally established as wrong though in Europe it was generally prohibited.

The reasons for slavery taking off during expansion are for a few reasons. Least not of all the muslims were doing it to christians with authorisation given to do to them as they do to us.

Though there are other reasons as well such as outside of Europe being outside of jurisdiction and that while others are still doing it, gaining a competitive advantage from it you can't rule it out entirely if you want to compete.

Still the 1500s were very different times to now and circumstances weren't such that it was reasonable to expect universal abolition of slavery. More of a patchwork with slavery on and off but even back then Europe was ahead and very progressive eventually culminating in the abolition of slavery.

It wasn't globally established as wrong though in Europe it was generally prohibited.

The reasons for slavery taking off during expansion are for a few reasons. Least not of all the muslims were doing it to christians with authorisation given to do to them as they do to us.

Though there are other reasons as well such as outside of Europe being outside of jurisdiction and that while others are still doing it, gaining a competitive advantage from it you can't rule it out entirely if you want to compete.

Still the 1500s were very different times to now and circumstances weren't such that it was reasonable to expect universal abolition of slavery.